Tolylene Diamine (TDA) Production Process Trace Water Removal Of Research

Toluene diamine (TDA) is the production of toluene diisocyanate(T DI) of the main raw material,through the photochemical reaction with phosgene Jinxing production TDI.TDA is through the production of dinitrotoluene(DNT) in the diatomaceous earth as a carrier of nickel hydrogenation catalyst,the reaction by-product is water. Hydrogenation of the material after the dehydration of crude after the dehydration, distillation separation obtained TDA, for the production. The reactor out of the reaction solution containing water, solvent,tar and other components and re-light points. If the moisture content is too high will accelerate the corrosion of equipment to make the system significantly increased the content of iron salt.The solvent DEIP under the iron salts reacted with phosgene and chloroethane CBC, while the reaction of CBC with toluene diamine amide viscous solid by-product of severe direct impact on the normal production,the production of TDA deep dehydration unit is to ensure normal production of the final product an important step in TDI. The scale of 100,000tons for the TDI unit,TDA 100ppm in the feed reduces the water content of each year TDI plant will be able to reduce the water into the nearly 8 tons. The water entering the system, not only consumption of raw materials, lower yield,more importantly,of safety,the company revamped the dehydration process optimization, the current TDA product has reached 200ppm less water, but under current conditions to continue to reduce water content requirements to foreign products (50ppm or less), the need for further research and development work. Therefore the use of tower installation for dehydration of the depth of TDA will be of great significance.In the study of this topic,the proposed reactor type and experimental method tower two dehydration through the samples by gas chromatography separation of the road,and detected with a thermal conductivity detector,through the external standard method for quantitative analysis,analytical techniques TDA products of water, quantitative analysis,to prove the objectivity of the results. Through continuous experimental analysis to study the nitrogen flow in a certain tower installation, temperature, and number of theoretical plates under the effect of dehydration on the TDA, TDA draw the remaining factors and the relationship curve of water, determined by this study With the nitrogen flow increases, dewatering will be good. With the increase in the number of theoretical plates, TDA reduction of the remaining water content trend will slow down. In the best conditions of various factors on the TDA-depth analysis of the results of dehydration, take the best option.